This invention relates to authentication with physical unclonable functions.
Physical Unclonable Functions (PUFs) in electronic circuits can be used to distinguish integrated circuits (ICs, “chips”) from one another. The ability to distinguish one chip from another using a PUF in hardware (a “Hard PUF”) or in a programmable device (a “Soft-PUF”) is a potentially valuable way to authenticate ICs. The applications for such authentication are wide ranging and include, among others, anti-counterfeiting, inventory control, multi-factor authentication (to allow access to computer system or on-line computer systems & networks), and, with appropriate control logic used in conjunction with a basic PUF circuit, secret key generation for cryptographic and other security applications. An effective authentication mechanism can be executed in a number of ways, but typically involves the use of digital challenges (strings of 1's and 0's) which, when applied to a typical PUF circuit, yield corresponding digital responses (another string of 1's and 0's) that differ from one integrated circuit to the next. These challenges and their corresponding responses are the challenge-response pairs (CRPs) for that PUF.